BEAVERTON —I spent a couple of hours last week in the footsteps of Lance Armstrong, Mia Hamm, Tiger Woods and Michael Jordan. And I didn't even leave Oregon.I was touring the beautiful, 193-acre campus surrounding Nike World Headquarters in Beaverton, eight miles west of downtown Portland.

In a stew, oysters keep the fresh mineral flavors of a raw bar — but with the plump texture of a cooked bivalve. It's a warming way to have the best of both worlds, in a simple and satisfying oyster stew. Here are four interpretations of a classic, with flavors from Japan, Mexico and New Orleans.